Precast slab with insulating insert



12, 1938.` l Q F DAVlS y y 2,114,048

" RRECAST SLAB WITH INSULATI'NGINSERT n .Filed May 1o, 19:53

ATTORNEY.

l* (Patented 1938 mesne assignments, to'Ameriean Cyanamid i ChemicalCorporatioma corpmfaticmA of Dcla-` c f ware'Y sound,` and a deck inwhich VsuchslabsareA used.

In applyinginsulation' of the `above time lto perienced in thatsuchlmaterialis usually ot a 1 broken. or mutilated. Hencefits`application to highbreakage'loss. f g y f1 insulating Amat'erialini-the form of `porous ompositions such as gypsum or concrete areapuplied as aplaster to walls or ceilings{.diiilculties kewise arise inthat the materialmust be ycareully` controlled inmixing or processing,`and sevdling, which 'means 'highly skilled` workmen,` and tionswili notstayA ony the wx'tilsorv ceilings evenly u and. this' involves theuse ofexpensive scaolding Vgmaterial; forms and the like.-y

" 'Itisone of the principal objects of thisinveni' factory made, towhichinsulationboth 4trol-r1 heat "and/or soundj may Vbe *applied eitherduring the i u making/of rthe slab r *at sometime subsequent v f theretobut prior Kto installation.` vSuch-a pro- Fcedure hasl distinct*advantagesA in` that no'L scatio'lding or forms are necessary onthe jobinasuch as the insulationis put in placealongwith ""the slab in theerection 'of the building. The lfact l that the entire Objectis factorymade facilitates Y its `manufacture withy theleast amount of handlingand hence `initial costs are kept atla 'mini- `Itis another obiectrofthe invention to provide da s'lab of the precast variety to which arelatively `fragile insulating insert will-be applied; the insert beingcompletely within the-contines of the slab 40itself so vasfto beentirely protected lduring han- 'dling andshipping. f L

Anotherimpcrtant'object ofthe invention is f the provision `of a Vslabof the precast type containing a section of insulating material of `ana- 4 ture which maybecast' therein in the factory and Lwliikzhvill beof such al composition as will yform an? eilective bond i* to theslab'without'iurther treatment. m

\ Another important object oi the invention =is' mrragile soundyms'umting insert-thereinyfhesab l of the slab. may form an effectiveceiling for the l 55 roomor space below, the metal edges of the slab '6wbuildings 'alreadyherecte some diiiiculty is exi .more'orless"delicateor *i'riablenatura` readiiy eralf coats must be applied because suchcomposif tion to provide a slab of the precast type; ythat is -To`this'end the inventioncontemplatesaslab of set cernentltious materialoi' which gypsum is typical, either `with or without fillers or admix ,l

50 the `provision of va precast-slab having a relatively #itself havingmetallic edgeswso that when such F slabs are used as aro'o'i orfioorytheunder side Application Mario, 193s, serial No. 670,235l

v c c g' `s write-ear The present inventic'nrelates 'to a precast slab joisetfcementitious material with which isincor- "1"lporatedvaninsulatingcfinsert `either for heat or llmpported directlyfrom the roof purlinsor 'filoor beams. -As arresult, neither thematerial of which the slab is m'ade'northe relatively fragile .yinsulating insert jmakes direct contact withfthe l supporting element,Lbut `on the vcontrary the 5 jweightfof the vslab isborne-principally bythe metaledg'ep n y c' 4 Stiilanotherobject oi the invention is therprof vvision'of a slab ofthe above type in which the' insulating inserthas a'suriace areav lessthan 10 the surface vareaoi' the slab to whichit is attachedg that is, the rslab proper will have a \mar' ginal edgeOfcementitious materialsurroundingl the insert.` Thisl constructionpermits the entire "insulating insert Ato' beexposed free from interl5tering purlins or beams wheresuch slabs are incorporated into a oor,ceiling or roof.y As a rereplacement or decoration.

to provide a slabof the above type rwhich may 'be used as iioor, roof,ceiling or wall' slabs with of, as a single slab oras two slabs facingeach other or baciato back.

tures ysuch as wood chips, fibers or the like,y hav` "ing achannelledface.V x'I'his channel may' eirtend i substantially the entire lengthand widthof lthe slab or it may be interrupted by cross ribsso thattherewill be several channels or depressions inra single slab.` f

'It is proposed in one form that aporous vcom 35 positionrthat is, acomposition of set material having bubbles orporesjtherein, eithercommunieating or non-communicating, be used asa iill-v lng for thiscavity, either w completely" fm the "channei'or depression 'or castseparately; cut to 4o proper dimensions and inserted into the cavity sothat the 'surface oi the insert isj substantially flush with thesurfaceof the slab face within which it is contained,` leaving anairspace between the bottom ,of the cavity of `the slab andthe back l5'l Vof the insulating insert. Where such jporousc'om- I `positionis ofmaterial involving Athe use `of'gry'psum,` it maybe readily bonded`tothe precast slabl of gypsum without any additional attentionbeing paidtosecuring means, that isfthe gypsumfslabto itself may iirst beca'stzand then "either beforeor after drying' the same the yporouscomposition poured therein', thel two being permitted to" set In stillanother modiilcation` the insulating in- 55 `It is another importantobjectof(` the invention; so f' sert may take the form of a more or lessrigid sheet of material of which'Celotex is typical.

Where sheet material is used. such as either Celotex or the cast slabsof a porous composition as above described, it is contemplated that thesides of the slab constituting the cavity will be stepped or providedwith a shoulder so that such inserts may be readily positioned withinthe cavslab, which edging shall extend over three faces so that when theslabs are supported on,V the purlins, beams or the like. the metalcovering will come in contact with the slab support rather than i thegypsum itself. This, therefore, prevents any undue cracking or spallingof the gypsum material. It is likewise desirable that opposite metalmembers be provided with complementary parts such as a tongue and grooveso thatwhen two slabs are erected adjacent' each other, their metalparts may interlock, not only to prevent undue'separation of the partsunder vibration but to cause a strengthening and supporting actionbetween the various slabs, andparticularly the ends thereof which occurbetween beam spacings. (This mating interlock may be provided on allfour edges or only on opposite edges, as circumstances will dictate. Theinvention further consists in the novel arrangement and construction ofparts4 more fully hereinafter described and shown in the drawing.

In the drawing- Fig. 1 is a plan view lof a slab of this invention withthe insert partially broken away.

Fig. 2 is a sectional view of a building construction involving theinvention of Fig. 1.

Fig. 3 is a fragmentary sectional elevation showing a modified form ofslab.

Fig. 4 is a sectional view of another form of insert.

Referring now with particularity to the embodiments illustrated, aprecast slab is shown at i of gypsum or the like with or without fillersand admixtures such as chips, fibers or the like, having a series ofcavities 2 in one face thereof. Obviously this cavity may extend as asingle depression over substantially the entire area of the slab face orit may be separated into a plurality of cavities such as shown in Fig.l, in which six cavities occur separated by ribs l.

In Fig. 2 the walls of this cavity are formed with a shoulder as at l,which permits the insertion of a heat and/or sound insulating section lthereinto, the bottom edge of the insert contacting with the shoulder I.By choosing an insert of the proper thickness and suitably positioningthe shoulder s during the manufacture of theslab l, the parts may bestandardized and put together with a minimum amount of effort. Wheredesired the insert 5 may be secured to the' slab as by means of nails 8or the like.

In this form shown in Fig. 2, the cavities in the face of the slab aredivided laterally thereof by,

means of the rib I so that two cavities occur across the slab. In suchcase the rib 3 preferably terminates short of the slab face so as toform an additional base or support for the center portion of the insertI.

Obviously by suitably proportioning the slab thickness, a space mayexist between the bottom of the cavity 2 and the back of the insert 5.'I'his air space has been found to be of considerable advantage from the`standpoint of insulation both for heat and sound. It will also beapparent that in some instances this air space may be cut down oradjusted yto the desired extent by suitably proportioning the thicknessof the top wail 1 of the slab I or the thickness of the insert B, orboth, as desired.

the patent to Sanford 230.151 of 1880 and those,

in the patent to Sabine and Guastivino 1.119.543 of 1914 are typical.Itis preferred, of course.

that if the precast slab is made of gypsum orV the llike orlpredominantly of gypsum, that such porous composition shall likewiseinclude sufiicient gypsum or other material of a nature that when theporous composition is pouredvinto the precast slab there will be anatural and effective bonding between the two bodies, making unnecessaryany further fastening devices. Experience hasl found that for the bestsound insulating effects the porous composition should be such that theporesr therein are intercommunicating, said ,n pores having substantialopenings at the surface.

This seems to produce an effect in which when sound impinges upon thesurface thereof, it passes into the cavities or pores and due to theircircuitous and tortuous nature. is trapped and lost or absorbed therein.y

It will be apparent, of course, that the pouring of this compositionpresents no great difficulties as a factory product. It is true, ofcourse, that porous compositions are of a relatively fragile nature andhence are easily broken or mutilated. The fact that the composition asshown in Fig. 4

has its surface flush with the surface of theslab, is a desirablecircumstance for the outer edges' of the more dense and rigid gypsumeffectively protect .the more delicate material therein from damage.When such slabs are shipped from the factory to the job or handled onthe Job, they may be laid one on the other and there is no real dangerof destruction or mutilation of lthe insulating material.

The sheet insulating insert oflig. 2 may be of any desired nature suchas the commercial Celotex now on the market, or it may even be f made ofa porous composition as described in connection with the insert s ofFig. 4. cast into "'Ihis protecting rnetaledgey may take the form of anVelement 9 covering oneuedge ofthe slab @and extendingas a flangeflllover oneface, the end Il'being turned down and embedded into yor thelike IZjengageable with acorresponding groove I3 on the lcomplementarymetal member attached to the opposite edge ofthe slab. 0bviously all ofthe edges of the slab may be thus provided. or only some.

` tofmetalcontact,lthat'is,flange |01of7the `metal of the beam o lng ofthe comparatively fragile inserti which would be the case `ii.' thatsheet'4 extended completely over the entire face of -the slab I.

the'slab toprevent4 separation therefrom. 'Ihe element 91 may also beprovided with a tongue `Inv erection, `referenceis made to Fig. 2 in"which,` slabs Aand B as Vabovedescribed are i. i inte'rlockecltogether` by means `of the `mating action ofthe metal'members '9 andaresupported from the beam or purlin IL As shown. the slabpropercontacts with the support I4 'by a metal is in direct contactwith-the flange elements 9 Il. This prevents any undue crush- Due tothis interlocking effect of the metal elements on adjacent slabs, aneffective I beam resultsl so that a single slab may extend well beyondtwo given beams or supports and the free end entirely supported and heldby the interlocking engagement therewith `of the surround-v ing slabs.'This makes for a very effective construction, rendering unnecessaryvthe `special designing of the steel work for `particular lengths ofslabs or vice versa. The Apresent slabs may,

therefore, be erected at random ywithout regard to beam spacing. .nThese inserts may be decorated orpainted with 'any' desired 'material-which will not destroy the i `porosity thereof to such anv extentk aswould de-s -l `tract .from the efficient `absorption of sound orprevention ofheat transmission. Such paint or `decoration may take theform of cold water mixtures Aorin fact vany material which will not oclose the pores.

5 as being p1aced with` their insert suis` down, as v `for instance inthe roof` of a large auditorium,

While in Fig. V2' .the slabs lhave*y been shown where the under face orthe slab forms the ceiling thereof; yet-obviously `it may be desirablein some instances to place the slabs of Fig. 2

in an up-side-down mannerjon the beams I4,

.as for instance in the oor of a building. In v such event a wood orother floor may be ap- 1 .plied directly l o out in any waydisturbingthe insert Bfand still "maintaining the effectiveness thereof. v

"In like mannerjthese slabs may be yused in` over the topof such slabwithpartitions` erected vertically, with the insulation f 5 or 8 at onesidefonly, ora slab of double thick-A ness havingy cavities on each sidethereof may be utilized effectively, or two slabs erected withy theirinserts facing each other.

By suitably v, spacing such slabs, or even slabs without inserts,

from each other, partitions or walls `of any ydesired thickness may behad with the use of slabs of 4a standardized thickness. Obviously moreinsulating ymaterial may be inserted between such slabs ii.'foundnecessary or desirable. It Vwill be obvious, of course, that ifduring the vening walls of eachof said` cavities.

course of time `these inserts become damaged or inefficient by reason ofthe 'clogging' of the pores, they maybe readily replaced byV simplytaking. them out and putting. new inserts inthe cavities.

' This may be done with the minimum amountrofv l effort and without inany manner destroying or disturbing the slabs within which they occur.Inasmuch as the` insulation inserts are of comparatively small4 extent,a large area neednot be replaced in case ofY damage to a- 1. A precastslab of set cementitiouslmaterial small part;

having'a cavity in'one face thereof and an in`r` `sulatinginsert locatedin said cavity in which" an air spacezexists between the slab body andokj.

the insert.

l 2. A precast slab of setcementitious material having a plurality of;cavities in one face thereof,` a web located between two adjacentcavities and insulation in each cavity and inl contact with the face ofsaidL web. i

3. A precast slab of set cementitious vmaterial having a pluralityrofcavities in one face thereof, a web located between twoadjacent cavitiesand sheet insulation bridging a plurality of cavities.

4. A precast slab of set cementitious material having a plurality ofcavities in one face thereof, aweb` locatedbetween two adjacentcavities` f and sheet insulation bridging a plurality of cavities andsupported by, said web.

5. A precast slab of set cementitious material having edge portions ofgreater thickness thana point intermediate said edges,v a cavity betweensaid edges, a shoulder between an edge and -a.

cavity and insulation materialv seated on said shoulder andvcoveringsaid cavity.

6. A precast slab of set cementitious material having edge portions ofgreater thickness than a point intermediate saidedges, a cavitylbetweensaidv edges, av shoulder between an edgeand all cavityv and insulationmaterial seated on said` y shoulder and covering said cavity, said slabhave.y

ing a web ofless thickness than theslab edge, said insulation being alsosupported by said web.

1. A building constructionincluding supporting elements, adeck`supported thereon, fsaid deck comprising a series of precast `slabs ofset cementitious material each slabr having a cavity in one face,linsulation in said cavity, the surfaceof the sound insulation beingflush` with the slab face, those portions of thesiab in ,con-.o tactwith the supporting element being covered 1 with metal.

8. An accoustical construction comprising a backing member having` itsfront area formed to providev a multiplicity of cavities and an inftervening cavity wall, and a facing of thin sheet," material coveringsaid cavities and ,being `secured to the front surface areas of the`inter- CLARKE Davis.;

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